Boom microphones are intended to be used very close to the speaker's lips to maximize the noise cancelling effect of the enclosed microphone capsules. Locating the microphone close to the lips often causes undesirable sounds to be generated. Certain speech sounds which produce high air velocities at the lips such as plosives (sounds such as p, t, and d) generate "puff noise". The noise is caused by the turbulence created when high air velocities coming from the lips strike the protective grid which is commonly provided to cover the microphone capsule. A prior art approach to reduce "puff noise" in currently available microphones is to place a layer of foam directly between the microphone element and the protective grid. The thickness of this layer of foam must be minimized to keep the microphone capsule close to the lips for good noise-cancelling effect. A certain amount of "puff noise" still passes through to the microphone capsule.
An object of this invention is to reduce the amount of puff noise associated with boom type microphones.